A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a func...A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a functional monomer for the selective separation of Ni(Ⅱ) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(Ⅱ) at the optimal p H of 7.0 was 66.22 mg·g^(-1). The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Cu(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pb(Ⅱ), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(Ⅱ) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(Ⅱ) in real water samples.展开更多
The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ...The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.展开更多
The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-(+)-leucinol with Ni(II) chloride and L-(-)-leucinol with Co(II) acetate tetra- hydrate in anhydrous met...The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-(+)-leucinol with Ni(II) chloride and L-(-)-leucinol with Co(II) acetate tetra- hydrate in anhydrous methanol. The crystal structures of I and II were determined by single-crystal X-ray diffraction and further characterized by elemental analysis and IR. For I: [Ni(C18H45N3O3)]Cl2, orthorhombic, P212121, a = 11.2807(9), b = 14.7115(11), c = 16.3580(13) A, V = 2714.7(4) A3, Z = 4, Pcalcd = 1.177 Mg/m3, the final R = 0.0407, and 16539 reflections observed with I 〉 2σ(/); For II: [Co(C45HI08N6015)], trigonal, R3:H, a = 23.981(3), b =23.981(3), c = 10.8925(15) A, γ = 120°, V = 5425.1(14) A3, Z = 3, Pcalcd = 1.002 Mg/m3, the final R = 0.0625 for 16556 observed reflections with I 〉 2σ(I). The complexes were then used to catalyze the Henry reaction and obtained good catalytic results. The catalytic activity of the complexes was determined by IH NMR. And research is going towards the application to other organic reactions such as cyanosilylation reaction.展开更多
The hydrothermal reaction of 1,2-bis(imidazol-1′-yl)ethane (Bime) and Ni(NO3)2·6H2O gave rise to a two-folded interpenetrating 3D coordination polymer, [Ni(Bime)3·(NO3)2]n. Singlecrystal X-ray dif...The hydrothermal reaction of 1,2-bis(imidazol-1′-yl)ethane (Bime) and Ni(NO3)2·6H2O gave rise to a two-folded interpenetrating 3D coordination polymer, [Ni(Bime)3·(NO3)2]n. Singlecrystal X-ray diffraction analyses show that the complex crystallizes in rhombohedral space group R-3. Ni(II) lies on a crystallographic S6 centre and connects six bimes into a 3D porous network. Bime exhibits an anti conformation. NO3- locates as the void filler to balance the charge in the system. The framework is stable through the two-folded interpenetration among the building units.展开更多
In this work, the synthesis and complexation properties of a new compound, 1,3-bis[5-(2-hydroxyphenyl)-4-phenyl- 1,2,4-triazole-3-yl-thio]propane (BTP), towards certain transition metal ions, (M(II) where M = Zn, Cu, ...In this work, the synthesis and complexation properties of a new compound, 1,3-bis[5-(2-hydroxyphenyl)-4-phenyl- 1,2,4-triazole-3-yl-thio]propane (BTP), towards certain transition metal ions, (M(II) where M = Zn, Cu, Ni) in acetonitrile is reported. A hard-modeling strategy was applied to UV-Visible spectroscopy data obtained from monitoring the reaction between BTP and the selected metal ions to determine the concentration profiles of each species and the corresponding stability constant(s) of the complex(es). The stability constants of complexes are always defined in terms of their free metal, free ligand and complexed forms. These constants are influenced by parameters such as the type of metal, ligand, counterion or solvent. In this study, the formation constants of the complexes were determined for the synthesized ligand with several metallic cations in acetonitrile solvent by UV-Vis spectrophotometry.展开更多
A two-phase anaerobic reactor fed with glucose substrate(3 g chemical oxygen demand(COD)/L) was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product(SMP...A two-phase anaerobic reactor fed with glucose substrate(3 g chemical oxygen demand(COD)/L) was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product(SMP) formation. Low concentrations of Ni(II)(5 and10 mg/L) promoted the acid phase, whereas high concentrations(15, 20, and 25 mg/L)exhibited an inhibitory effect on, but did not alter the fermentative method, which mainly involved the fermentation of propionic acid. The methanogenic microorganism exhibited a strong capability adapting constantly increased Ni(II) levels. The acid phase was an accumulation stage of SMP. In the absence of Ni(II), the high-molecular-weight material in the effluent SMP mainly contained polysaccharide, tryptophan, and casein. Methanogens metabolized most of the polysaccharide, the whole tryptophan content, and part of the casein, leading to the presence of humic acid and protein in effluent. After Ni(II) dosage, the protein and polysaccharide of the acid phase increased, and tryptophan changed, while casein remained stable. More protein than polysaccharide was produced, suggesting the prominent function of protein when addressing the negative effect of toxic metals. The analysis of DNA confirmed the change of bacterial activity.展开更多
A new complex, [Ni(acac)2(NITQ)2]-2CH2C12 1 (acac = acetylacetone, NITQ = 2-(2"-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide), was synthesized and charac- terized by elemental analysis, IR spec...A new complex, [Ni(acac)2(NITQ)2]-2CH2C12 1 (acac = acetylacetone, NITQ = 2-(2"-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide), was synthesized and charac- terized by elemental analysis, IR spectroscopy, UV-Vis absorption spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 9.6970(19), b = 20.410(4), c = 12.166(2) A, β = 93.89(3)°, Mr = 997.43, V= 2402.3(8) A3, Z = 2, Dc = 1.379 g/cm3, F(000) = 1040,μ = 0.684 mm-1, the final R = 0.0423 and wR = 0.1197 for 2884 observed reflections (1 〉 2σ(I)). Compound 1 is found to assume a mononuclear structure, which is further linked into a three-dimensional (3D) supramolecular network by hydrogen-bonding, C1...O weak contact and π...π stacking interactions. Moreover, the luminescent properties of the ligand and compound 1 were further investigated in detail.展开更多
The asymmetric a-sulfenylation of Ni(II) complex of glycine with S-substituted 4-methylbenzenesulfonothioate is reported. Due to the mild and simple reaction conditions, this asymmetric reaction is compatible with v...The asymmetric a-sulfenylation of Ni(II) complex of glycine with S-substituted 4-methylbenzenesulfonothioate is reported. Due to the mild and simple reaction conditions, this asymmetric reaction is compatible with various functional groups.展开更多
A new Ni(II) coordination polymer [Ni(L)2(SCN)2]n(L = 1,4-bis(benzimidazol-1-yl)butane) was synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The...A new Ni(II) coordination polymer [Ni(L)2(SCN)2]n(L = 1,4-bis(benzimidazol-1-yl)butane) was synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group C2/c with a = 9.4760(3), b = 24.0408(8), c = 16.5871(5) A, β = 99.832(3)°, V = 3723.2(2) A3, Z = 4, Dc = 1.348 g/cm3, F(000) = 1576, the final R = 0.0486 and w R = 0.0936 for 2938 observed reflections with I 】 2σ(I) for the complex. Structural analysis shows that the coordination polymer possesses a 2D(4,4) layer structure which is composed of Ni(II) centers bridged by L ligand with two kinds of conformations and further assembled into a 3D supramolecular network via π-π stacking interactions. In addition, the fluorescence and catalytic properties, for the degradation of Congo red, of the complex were investigated.展开更多
The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to mo...The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to monoclinic, space group P21 with a = 13.208(1), b = 10.741(1), c = 19.398(1) ? b = 104.39(1)o, V = 2665.8(4) 3, Z = 4, Dc = 1.435 g/cm3, m(MoKa) = 0.780 mm-1 and F(000) = 1198. The final R = 0.0504 and wR = 0.1267 for 9159 observed reflections (I > 2s(I)), and R = 0.065 and wR = 0.1299 for 11006 independent reflections. The complex assumes a distorted octa- hedral coordinate geometry formed by one aspartate dianion and three benzimidazole ligands. The aspartate chelates to the Ni atom as a tridentate ligand. The lattice water molecules are hydrogen- bonded to the Ni complex molecule.展开更多
文摘A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a functional monomer for the selective separation of Ni(Ⅱ) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(Ⅱ) at the optimal p H of 7.0 was 66.22 mg·g^(-1). The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Cu(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pb(Ⅱ), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(Ⅱ) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(Ⅱ) in real water samples.
文摘The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.
文摘The title nickel complex I and cobalt complex II were obtained separately from the direct reaction of D-(+)-leucinol with Ni(II) chloride and L-(-)-leucinol with Co(II) acetate tetra- hydrate in anhydrous methanol. The crystal structures of I and II were determined by single-crystal X-ray diffraction and further characterized by elemental analysis and IR. For I: [Ni(C18H45N3O3)]Cl2, orthorhombic, P212121, a = 11.2807(9), b = 14.7115(11), c = 16.3580(13) A, V = 2714.7(4) A3, Z = 4, Pcalcd = 1.177 Mg/m3, the final R = 0.0407, and 16539 reflections observed with I 〉 2σ(/); For II: [Co(C45HI08N6015)], trigonal, R3:H, a = 23.981(3), b =23.981(3), c = 10.8925(15) A, γ = 120°, V = 5425.1(14) A3, Z = 3, Pcalcd = 1.002 Mg/m3, the final R = 0.0625 for 16556 observed reflections with I 〉 2σ(I). The complexes were then used to catalyze the Henry reaction and obtained good catalytic results. The catalytic activity of the complexes was determined by IH NMR. And research is going towards the application to other organic reactions such as cyanosilylation reaction.
基金supported by the National Natural Science Foundation of China (20971101)
文摘The hydrothermal reaction of 1,2-bis(imidazol-1′-yl)ethane (Bime) and Ni(NO3)2·6H2O gave rise to a two-folded interpenetrating 3D coordination polymer, [Ni(Bime)3·(NO3)2]n. Singlecrystal X-ray diffraction analyses show that the complex crystallizes in rhombohedral space group R-3. Ni(II) lies on a crystallographic S6 centre and connects six bimes into a 3D porous network. Bime exhibits an anti conformation. NO3- locates as the void filler to balance the charge in the system. The framework is stable through the two-folded interpenetration among the building units.
文摘In this work, the synthesis and complexation properties of a new compound, 1,3-bis[5-(2-hydroxyphenyl)-4-phenyl- 1,2,4-triazole-3-yl-thio]propane (BTP), towards certain transition metal ions, (M(II) where M = Zn, Cu, Ni) in acetonitrile is reported. A hard-modeling strategy was applied to UV-Visible spectroscopy data obtained from monitoring the reaction between BTP and the selected metal ions to determine the concentration profiles of each species and the corresponding stability constant(s) of the complex(es). The stability constants of complexes are always defined in terms of their free metal, free ligand and complexed forms. These constants are influenced by parameters such as the type of metal, ligand, counterion or solvent. In this study, the formation constants of the complexes were determined for the synthesized ligand with several metallic cations in acetonitrile solvent by UV-Vis spectrophotometry.
基金supported by the National Natural Science Foundation of China (Nos. 51178215 and 51378251)the Jiangsu Nature Science Fund (No. BK2011032)+2 种基金Open Science Foundation of Jiangsu (No. 50808121)the National Science and Technology Major Project for Water Pollution Control and Treatment (No. 2012ZX07301-005)the 2012 Scientific Research Open Found of Jiangsu Key Laboratory of Environmental Engineering
文摘A two-phase anaerobic reactor fed with glucose substrate(3 g chemical oxygen demand(COD)/L) was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product(SMP) formation. Low concentrations of Ni(II)(5 and10 mg/L) promoted the acid phase, whereas high concentrations(15, 20, and 25 mg/L)exhibited an inhibitory effect on, but did not alter the fermentative method, which mainly involved the fermentation of propionic acid. The methanogenic microorganism exhibited a strong capability adapting constantly increased Ni(II) levels. The acid phase was an accumulation stage of SMP. In the absence of Ni(II), the high-molecular-weight material in the effluent SMP mainly contained polysaccharide, tryptophan, and casein. Methanogens metabolized most of the polysaccharide, the whole tryptophan content, and part of the casein, leading to the presence of humic acid and protein in effluent. After Ni(II) dosage, the protein and polysaccharide of the acid phase increased, and tryptophan changed, while casein remained stable. More protein than polysaccharide was produced, suggesting the prominent function of protein when addressing the negative effect of toxic metals. The analysis of DNA confirmed the change of bacterial activity.
基金Supported by the National Natural Science Foundation of China(No.21071006)the Natural Science Foundation of Henan Province(No.102102210457)the Natural Science Foundation of the Henan Higher Education Institutions of China(No.2010B150001)
文摘A new complex, [Ni(acac)2(NITQ)2]-2CH2C12 1 (acac = acetylacetone, NITQ = 2-(2"-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide), was synthesized and charac- terized by elemental analysis, IR spectroscopy, UV-Vis absorption spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 9.6970(19), b = 20.410(4), c = 12.166(2) A, β = 93.89(3)°, Mr = 997.43, V= 2402.3(8) A3, Z = 2, Dc = 1.379 g/cm3, F(000) = 1040,μ = 0.684 mm-1, the final R = 0.0423 and wR = 0.1197 for 2884 observed reflections (1 〉 2σ(I)). Compound 1 is found to assume a mononuclear structure, which is further linked into a three-dimensional (3D) supramolecular network by hydrogen-bonding, C1...O weak contact and π...π stacking interactions. Moreover, the luminescent properties of the ligand and compound 1 were further investigated in detail.
基金We gratefully acknowledge financial support from the National Natural Science Foundation of China (Nos. 81620108027, 21632008, 21472209, 21672231 and 81220108025), the Major Project of Chinese National Programs for Fundamental Research and Development (No. 2015CB910304), National S&T Major Projects (No. 2014ZX09507002-001), and the State Key Laboratory of Bioorganic Chemistry.
文摘The asymmetric a-sulfenylation of Ni(II) complex of glycine with S-substituted 4-methylbenzenesulfonothioate is reported. Due to the mild and simple reaction conditions, this asymmetric reaction is compatible with various functional groups.
基金supported by the Starting Research Fund from Hebei United University(35398599)the Natural Science Foundation of Hebei Province(B2014209182)
文摘A new Ni(II) coordination polymer [Ni(L)2(SCN)2]n(L = 1,4-bis(benzimidazol-1-yl)butane) was synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group C2/c with a = 9.4760(3), b = 24.0408(8), c = 16.5871(5) A, β = 99.832(3)°, V = 3723.2(2) A3, Z = 4, Dc = 1.348 g/cm3, F(000) = 1576, the final R = 0.0486 and w R = 0.0936 for 2938 observed reflections with I 】 2σ(I) for the complex. Structural analysis shows that the coordination polymer possesses a 2D(4,4) layer structure which is composed of Ni(II) centers bridged by L ligand with two kinds of conformations and further assembled into a 3D supramolecular network via π-π stacking interactions. In addition, the fluorescence and catalytic properties, for the degradation of Congo red, of the complex were investigated.
文摘The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to monoclinic, space group P21 with a = 13.208(1), b = 10.741(1), c = 19.398(1) ? b = 104.39(1)o, V = 2665.8(4) 3, Z = 4, Dc = 1.435 g/cm3, m(MoKa) = 0.780 mm-1 and F(000) = 1198. The final R = 0.0504 and wR = 0.1267 for 9159 observed reflections (I > 2s(I)), and R = 0.065 and wR = 0.1299 for 11006 independent reflections. The complex assumes a distorted octa- hedral coordinate geometry formed by one aspartate dianion and three benzimidazole ligands. The aspartate chelates to the Ni atom as a tridentate ligand. The lattice water molecules are hydrogen- bonded to the Ni complex molecule.